JP2701681B2 - Method for producing resin molded product and molding die apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin molded product obtained by integrally molding different resin materials, and more particularly to a method of manufacturing the same and a molding die apparatus.

[0002]

2. Description of the Related Art Conventionally, different resin materials are integrally molded by using a mold as follows. That is,
As shown in FIG. 8, after clamping the upper fixed mold 31 and the lower first movable mold 32, a kind of resin material 34 is injected into the cavity 33 between the both 31 and 32. .
Next, as shown in FIG. 9, the first movable mold 32 is replaced with the second movable mold 35, and the two molds 31, 35 are clamped, so that the two molds 31, 35 and the resin described above are formed. Material 3
4 and a new cavity 36 is formed. continue,
As shown in FIG. 10, another type of resin material 37 is injected into the new cavity 36. Thereby, the different resin materials 34 and 37 are integrally joined and molded. Then, by opening the fixed mold 31 and the second movable mold 35, a resin molded product made of different resin materials 34 and 37 is obtained. Here, a resin molded product for a cowl louver top for an automobile is obtained.

However, the above-described manufacturing method requires first and second movable molds 32 and 35. Further, since the two movable molds 32 and 35 are used interchangeably, not only the entire mold apparatus becomes large, but also the molding cycle until one resin molded product is obtained becomes long. .

Therefore, as a technique for integrally molding different resin materials without using two movable dies as described above, there is a technique disclosed in Japanese Patent Publication No. 63-44046, for example. In the technology of this publication,
A slide core is provided in one of the two molds to be clamped, and a resin material different before and after moving the slide core to a cavity formed between the two molds and the slide core by the mold clamping. By injecting
One resin molded product is obtained.

[0005] Therefore, it is conceivable to produce the same resin molded product for the cowl louver top by employing the technique disclosed in this publication. That is, as shown in FIG.
Is provided. When the upper mold 43 and the lower mold 41 are clamped, the upper end of the slide core 42 is placed in contact with the upper mold 43, and the upper and lower molds 41,
The first cavity 45 is formed by the
To form Next, from that state, as shown in FIG. 12, a kind of resin material 46 in the first cavity 45 is injected. In this state, a rib 47 having a hook-shaped cross section is formed at the tip of the resin material 46 due to the shape of the first cavity 45. Subsequently, as shown in FIG. 13, by moving the upper end of the slide core 42 to the lower end of the rib 47, a second cavity 48 is formed.
A different resin material 49 is injected into 8. As a result, the different resin materials 46 and 49 are integrally joined and molded. Thereafter, by opening the upper and lower molds 43 and 41, a resin molded product made of different resin materials 46 and 49 is obtained. Further, since different resin materials 46 and 49 are joined at the thick rib 47,
The bonding area of 6, 49 is increased, and stronger bonding is possible.

[0006]

However, in the latter technique described above, when the slide core 42 is moved downward, the upper end thereof merely coincides with the lower end of the rib 47. Therefore, the slide core 42 and the rib 47
There is a possibility that a resin material 49 injected into the second cavity 48 may leak out of the gap from the gap, thereby causing burrs. Also, slide core 4
Since a delicate gradient is usually set in the rubbing surface 50 between the mold 2 and the mold 41 provided with the mold, a gap is generated. Accordingly, there is a possibility that the resin materials 46 and 49 may enter the gaps due to the gradient, and the slide core 42
Not only did it worsen its own movement, but it also caused burrs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and a first object of the present invention is to reduce the size of a mold apparatus and shorten a molding cycle when molding different resin materials firmly and integrally. It is an object of the present invention to provide a method for producing a resin molded product that can be molded without generating burrs.

[0008] A second object of the present invention is to form a compact and firmly different resin material without causing burrs while always reducing the size of the mold apparatus and shortening the molding cycle. It is an object of the present invention to provide a molding apparatus for molding a resin molded product that can be used.

[0009]

In order to achieve the first object, in the first invention, a slide core is provided on one of two molds, and the two molds and the slide are fixed by mold clamping. For the cavity formed between the core and
In a manufacturing method of integrally molding one resin molded product by injecting different resin materials before and after moving the slide core, two molds are clamped and formed between both molds and the slide core. The first resin material is injected into the cavity to form an intermediate molded product having a rib at the tip, and then the slide core is moved so that the tip portion overlaps a part of the rib, and the slide core is moved in the moved state. The intent is to inject a second resin material into the formed cavity and to mold the second resin material integrally with the intermediate molded product.

In order to achieve the second object, according to a second aspect of the present invention, a first mold and a second mold to be clamped are provided.
A mold, a slide core provided in the first mold, and an urging block provided in the first mold and for urging the slide core in a direction orthogonal to the moving direction by the urging means.
A first cavity formed between the two dies and the slide core in a state where the first and second dies are clamped and having a rib space for forming a rib at a tip thereof; A first gate for injecting the first resin material, and a state in which the first resin material is injected into the first cavity, the slide core is moved so that a tip portion thereof overlaps a part of the rib space. A second cavity formed by
A second gate for injecting a second resin material into the second cavity is provided.

[0011]

According to the first aspect of the invention, the first resin material is injected into the cavity between the two clamped molds and the slide core, so that the intermediate molding having the rib at the tip end. An object is formed. Then, the second resin material is injected into the cavity formed by moving the slide core from that state, and the second resin material and the intermediate molded product are integrally formed. At this time, since the leading end of the slide core is arranged so as to overlap a part of the rib, there is no gap between the end of the rib and the leading end of the slide core. In addition, since the intermediate molded product and the second resin material are joined at the rib portion which is thicker than the others, the joining area is increased.

According to the above configuration, two molds and a slide core are used to integrally mold different resin materials, and the slide core is only moved after one mold clamping. As compared with the case where a movable mold is used, the entire mold apparatus becomes smaller, and the molding cycle for one resin molded product becomes shorter.

According to the configuration of the second invention, the first resin material is injected from the first gate into the first cavity between the first and second molds and the slide core, which are clamped. As a result, an intermediate molded product made of the same resin material is obtained. Also, due to the rib space in the first cavity,
A rib is formed at the tip of the intermediate molded product. Then, the second cavity is formed by moving the slide core from that state, and the second resin material is injected from the second gate into the second cavity, thereby forming the second cavity.
The resin material and the intermediate molded product are integrally formed. At this time, since the leading end of the slide core is arranged so as to overlap a part of the rib space, there is no gap between the end of the rib of the intermediate molded product and the leading end of the slide core.
In addition, the intermediate molded product and the second
And the resin material is joined, so that the joint area is increased. Further, since the slide core is urged through the urging block by the action of the urging means in a direction orthogonal to the moving direction of the slide core, between the slide core and the urging block or between the slide core and the first metal. There is no gap between the mold.

According to the above configuration, in molding different resin materials integrally, two molds and one of them are provided with a slide core, and the slide core is moved only after one mold clamping. As compared with the case where two movable molds are used, the entire mold apparatus is reduced, and the molding cycle for one resin molded product is shortened.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the method of manufacturing a resin molded article and the molding apparatus in the first and second aspects of the present invention are embodied in a cowl louver top for an automobile will be described below with reference to FIGS. 7 will be described in detail.

FIG. 5 is a perspective view showing a state in which a cowl louver top 1 as a resin product in this embodiment is arranged on an automobile 2, and FIG. 6 is a perspective view showing one of them.
Cowl louver top 1 consists of left and right split pieces 3 and 4,
The divided pieces 3 and 4 are connected to each other at a connecting portion 5. In the width direction of the automobile 2, a large number of air holes 6 are formed vertically and horizontally in a central portion of the cowl louver top 1, and each air hole 6 is covered by a net 7. On one side edge of the cowl louver top 1, a glass fitting groove 9 for fitting the flotted glass 8 is formed.

FIG. 7 is a sectional view taken along line AA of the divided piece 3 of FIG. In the figure, the left end of the divided piece 3 is a glass fitting groove 9 into which the windshield 8 is fitted. The divided piece 3 of this embodiment is composed of a main body 10 made of a resin material different from the other, and a hook-shaped edge 11 having a glass fitting groove 9. That is, the main body 10
Is a relatively hard first material such as polypropylene (f-PP).
Of the resin material 12. On the other hand, edge 11
Is a styrene-
Ethylene-butadiene-styrene copolymer resin (SEB
The second resin material 13 such as E) is relatively soft. A rib 14 is formed at the tip of the main body 10, and an engagement protrusion 15 is formed adjacent to the rib 14.
Are formed. And, by the engagement projection 15,
The cowl louver top 1 is engaged with the body of the automobile 2.

Next, the cowl louver top 1 as described above is used.
The molding die apparatus for the divided pieces 3 and 4 will be described. FIG. 1 is a sectional view showing a part of the molding apparatus. This mold apparatus includes a lower first mold 16 and an upper second mold 17, so that both molds 16 and 17 are clamped and opened. The first mold 16 includes a main body block 18 and an urging block 19, and a slide core 20 that can move in the vertical direction is provided between the blocks 18 and 19. A concave portion 19a is formed on the base end side of the urging block 19, and a concave portion 18a is also formed on the main body block 18 corresponding thereto. Further, a spring 21 as an urging means is interposed between the concave portions 18a and 19a. And that spring 2
Due to the urging force of 1, the distal end wall 19b of the urging block 19 is constantly pressed against one side wall 20a of the slide core 20. That is, the slide core 20 is urged by the urging block 19 in a direction orthogonal to the moving direction (up-down direction). The other side wall 2 of the slide core 20 is urged by the slide core 20 as described above.
0b is always pressed against the side wall 18b of the main body block 18.

The slide core 20 divides a cavity formed between the first and second molds 16 and 17 into two parts over time. That is, as shown by a solid line in FIG.
In the state where the upper end of is placed in contact with the second mold 17,
A first cavity 22 for molding the main body 10 of the divided pieces 3 and 4 is formed. The first cavity 22 has a rib space 22a for forming the rib 14 described above.
, And a projection space 22b for forming the engagement projection 15 is provided. The second die 17 has a first gate 23 for injecting the first resin material 12 into the first cavity 22. On the other hand, as shown by a two-dot chain line in FIG. 1, when the slide core 20 is moved so that the tip thereof overlaps a part of the rib space 22a, the second cavity 24 for molding the edge 11 is formed. Are formed adjacent to the first cavity 22. In this embodiment, the overlap width α between the slide core 20 and the rib space 22a is
Is set to “1 mm”. The second mold 17 is provided with a second gate 25 for injecting the second resin material 13 into the second cavity 24.

Next, a method of manufacturing the divided pieces 3 and 4 using the molding apparatus having the above-described configuration will be described. In order to form the divided pieces 3 and 4 of the cowl louver top 1, first, as shown by a solid line in FIG.
6 and the second mold 17 are clamped, and in this state, the upper end of the slide core 20 is placed in contact with the second mold 17. Thereby, a first cavity 22 for molding the main body 10 of the divided pieces 3 and 4 is formed between the two dies 16 and 17 and the slide core 20.

Subsequently, as shown in FIG. 2, the first resin material 12 is injected into the first cavity 22 from the first gate 23. Thereby, the rib 14 and the engagement protrusion 15
The main body 10 is formed as an intermediate molded product having the following.
In this state, the slide core 20 is
9 presses against the side wall 18b of the main body block 18.

Then, as shown in FIG. 3, the slide core 20 is moved and arranged so that the tip portion thereof overlaps a part of the rib 14. Thereby, the second cavity 24 for obtaining the edge 11 of the divided pieces 3 and 4 is formed between the main body 10 as the intermediate molded product, the two dies 16 and 17, and the slide core 20.

Thereafter, as shown in FIG. 4, the second cavity 25 is moved from the second gate 25 to the second resin material 1.
Inject 3. As a result, the edge 11 having a hook-shaped cross section is joined to the main body 10 and molded.

Finally, after the molded product is cooled and solidified from the above state, the molds 16 and 17 are opened to take out the resin molded product. The divided pieces 3 and 4 in which the part 11 is integrally formed are obtained. Then, the cowl louver top 1 is obtained by connecting the left and right divided pieces 3 and 4 with the connecting portion 5.

As described above, according to the molding die and the manufacturing method of this embodiment, the edge portion 11 is joined to the main body portion 10 formed by the first cavity 22, and the two portions 10 and 11 are joined. Molded integrally. At this time, since the body portion 10 and the edge portion 11 are joined at the portion of the rib 14 which is thicker than the other portions, the joint area is increased, and
0, 11 can be more firmly joined.

Further, when the edge 11 is formed, the tip of the slide core 20 is arranged so as to overlap a part of the rib 14, so that there is a gap between the rib 14 and the tip of the slide core 20. There is nothing you can do. For this reason, the second resin material 13 injected into the second cavity 24 does not leak out from the gap, and the occurrence of burrs during molding can be prevented.

Further, the slide core 20 is constantly urged by the urging block 20 in a direction orthogonal to the moving direction. Therefore, before and after the slide core 20 is moved, there is no more gap than necessary between the slide core 20 and the block body 18 or between the slide core 20 and the urging block 19. That is,
The rubbing surface between the slide core 20 and the main body block 18 or the rubbing surface between the slide core 20 and the urging block 19 has a subtle gradient. No gap is generated. Therefore, each of the resin materials 12, 1
3 does not invade, and in that sense, it is possible to prevent burrs from being generated when the divided pieces 3 and 4 are formed. Further, since the resin materials 12 and 13 do not enter the rubbing surfaces, the movement of the slide core 20 itself is not hindered by the resin materials 12 and 13 and the slide core 20 always operates smoothly. Molding can be performed.

In addition, according to the molding die and the manufacturing method described above, when the different resin materials 12 and 13 are integrally molded, the two molding dies 16 and 17 and the slide core 20 are used once. The slide core 20 is simply moved after the mold clamping. Therefore, as compared with the case where two movable dies are exchanged and used, the entire die apparatus is reduced, and the molding cycle for one of the divided pieces 3 and 4 is shortened.

It should be noted that the present invention is not limited to the above-described embodiment, and may be carried out as follows, with a part of the configuration being appropriately changed without departing from the spirit of the invention. (1) In the above embodiment, in order to form the divided pieces 3 and 4 of the cowl louver top 1, after the hard first resin material 12 is injected into the first cavity 22, the second cavity 24 is softened. Of the second resin material 13 is injected. On the other hand, depending on the resin molded product to be molded, the order of injection of the hard resin material and the soft resin material into the first cavity and the second cavity may be reversed.

(2) In the above embodiment, the hard resin material 12 and the soft second resin material 13 are used as the different resin materials. Regardless, if a different resin material is used, the present invention can be embodied in other cases.

(3) In the above embodiment, the urging block 19
Although the spring 21 is used as the urging means, the urging means may be hydraulic. (4) In the above-described embodiment, the manufacturing method and the molding die for molding the divided pieces 3 and 4 of the cowl louver top 1 as a resin molded product are embodied. The present invention may be embodied in a manufacturing method and a molding die for molding a product or an interior product such as an instrument panel.

[0032]

As described above in detail, according to the first aspect, the first resin material is injected into the cavity between the two molds to be clamped and the slide core, and the rib is formed at the tip. Is formed. Next, a second resin material is injected into a cavity formed by moving the slide core so that the tip portion thereof overlaps a part of the rib, and the second resin material is molded integrally with the intermediate molded product. ing. Therefore, there is no gap between the end of the rib and the tip of the slide core. Further, only by moving the slide core after one mold clamping, different resin materials are joined to each other in a wide area. As a result, when molding different resin materials firmly, it is possible to reduce the size of the mold apparatus and shorten the molding cycle, and at the same time, it is possible to perform molding without generating burrs. Demonstrate.

According to the second aspect of the present invention, the slide core is always urged by the urging block in a direction orthogonal to the moving direction, and the first and second dies and the slide core are clamped by the mold clamping. Then, a first cavity having a rib space at the tip is formed. Then, after injecting the first resin material from the first gate into the first cavity, the second core is formed by moving the slide core so that the tip portion thereof overlaps a part of the rib space. The second resin material is injected from the second gate. Therefore, there is no gap between the end of the rib formed from the first resin material and the tip of the slide core. Also, there is no gap between the slide core and the urging block or between the slide core and the first mold. Furthermore, by simply moving the slide core after one mold clamping, different resin materials are joined to each other in a wide area. As a result, when molding different resin materials firmly and integrally, it is possible to reduce the size of the mold apparatus and shorten the molding cycle, and to perform molding with smooth operation without generating burrs. It has an excellent effect.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a part of a molding die apparatus according to an embodiment that embodies the first invention and the second invention.

FIG. 2 is a cross-sectional view showing a part of a molding die apparatus for explaining a molding order of a resin molded product in one embodiment.

FIG. 3 is a cross-sectional view showing a part of a molding die apparatus for explaining a molding order of a resin molded product in one embodiment.

FIG. 4 is a cross-sectional view showing a part of a molding die apparatus for explaining a molding order of a resin molded product in one embodiment.

FIG. 5 is a perspective view showing a state in which a cowl louver top is arranged in an automobile in one embodiment.

FIG. 6 is a perspective view showing a divided piece of a cowl louver top in one embodiment.

FIG. 7 is a sectional view taken along line AA of FIG. 6 in one embodiment.

FIG. 8 is a cross-sectional view showing a part of a mold apparatus for explaining a molding order of a resin molded product in a conventional technique.

FIG. 9 is a cross-sectional view showing a part of a mold apparatus for explaining a molding order of a resin molded product in a conventional technique.

FIG. 10 is a cross-sectional view showing a part of a mold apparatus for explaining a molding order of a resin molded product in a conventional technique.

FIG. 11 is a cross-sectional view showing a part of a mold apparatus for explaining a molding order of a resin molded product in another conventional technique.

FIG. 12 is a cross-sectional view showing a part of a mold apparatus for explaining a molding order of a resin molded product in another conventional technique.

FIG. 13 is a sectional view showing a part of a mold apparatus for explaining a molding order of a resin molded product in another conventional technique.

[Description of Signs] 3, 4 ... divided pieces as resin molded products, 12 ... first resin material, 13 ... second resin material, 14 ... ribs, 16 ... first
Mold 17; second mold 19; urging block 20
... Slide core, 21 ... Spring as urging means,
22: first cavity, 22a: rib space, 23: first gate, 24: second cavity, 25: second gate.

Claims (2)

(57) [Claims] 1. A slide core (20) is provided on one of two molds (16, 17), and the mold is clamped between the two molds (16, 17) and the slide core (20). Different resin materials (12, 13) are injected into the cavities (22, 24) formed before and after moving the slide core (20) to form one resin molded product (3, 3).
4) In a manufacturing method of integrally molding, the two molds (16, 17) are clamped, and a cavity formed between the molds (16, 17) and the slide core (20). (22) First resin material (1
2) is injected to form an intermediate molded product (10) having a rib (14) at the tip, and then the slide core (20) is formed.
Is moved so that its tip part overlaps a part of the rib (14), and the second resin material (13) is injected into the cavity (24) formed in the moved state, and the second resin A method for producing a resin molded product, comprising molding a material (13) integrally with the intermediate molded product (10). 2. A first mold (16) and a second mold (17) to be clamped, and a slide core (2) provided on the first mold (16).
0); a biasing means (21) provided on the first mold (16).
And an urging block (19) for urging the slide core (20) in a direction orthogonal to the moving direction of the slide core (20), and both dies in a state where the first and second dies (16, 17) are clamped. Mold (16, 17) and the slide core (2)
0) and a rib space (22) for forming a rib.
a) at the tip thereof, and a first resin material (1) in the first cavity (22).
2) a first gate (23) for injecting the first core material (23); and a state in which the first resin material (12) is injected into the first cavity (22).
0) is moved so that its tip portion overlaps a part of the rib space (22a), and a second resin material (2) is formed in the second cavity (24). 1
3) A mold apparatus for molding a resin molded product, comprising: a second gate (25) for injecting the resin.